A teenage girl with autism facing deportation after eight years living in Australia has been granted permanent residency, following an eleventh-hour intervention by the Assistant Immigration Minister.

Sumaya Bhuiyan, 16, had been ordered to book her flight out of the country by Friday, February 24. Her family's application for permanent residency was rejected in 2013 after immigration health checks found Sumaya had a "moderate developmental delay" that would result in significant cost to Australian taxpayers, her mother Nasrin Haque told Fairfax Media on Thursday.

But on Friday, the Assistant Minister for Immigration, Alex Hawke, reconsidered his refusal to intervene, and granted Sumaya permanent residency.

Dr Haque said she burst into tears when Mr Hawke called her with the news. "I feel better, much better today," Dr Haque said.

Assistant Minister for Immigration Alex Hawke had previously decided intervening in Sumaya's case was not in the public interest. Photo: Andrew Meares

"Really, I have been going through a stressful situation for so many months, it has been terrible. But this is great news."

A spokeswoman for Mr Hawke said the minister has also begun consideration of the same visa for Dr Haque and her son Sakir, subject to the usual character and health tests.

Dr Haque, a Blacktown GP working in two medical practices in Sydney, tried every avenue to appeal against the 2013 decision not to grant her family residency, including writing to the Immigration Minister to request intervention. Under section 351 of the Migration Act 1958, the Minister has the power to overturn immigration decisions if he or she thinks it is in the public interest to do so.

In January she was advised Mr Hawke had decided it was "not in the public interest" to intervene, and that Sumaya must leave the country.

Mr Hawke said on Friday that cases like Dr Haque's were "always complex" and involve many factors including immigration history, health, character and other issues.

"In some cases, all of the relevant information is not immediately available and a final decision can only be made after all matters have been thoroughly considered," he said.

Autism Awareness Australia chief executive Nicole Rogerson said Australia was lucky to have the Haque family and thanked the Assistant Minister for intervening.

"We are delighted Sumaya now has a permanent home in Australia," she said.

"It takes a brave politician to admit a policy error was made. He listened to our community and then acted to right a wrong. That's a pretty good politician in my books."

Ms Haque's local MP, Susan Templeman, said Mr Hawke's decision was in the best interest for both the family and the wider community. Ms Templeman has been helping with Dr Haque's appeal since being made aware of the family's plight in late 2016.

"I am so pleased that the Assistant Minister has decided to allow Sumaya to stay in Australia with her family," she said.

She said the Haque family had already made a big contribution to the country through Dr Haque's "incredible service" to her local community.

"We are a nation that has been built on immigration. Dr Haque and her family are exactly the type of immigrants that Australia needs," she said.